Dear Dr. Magnus Ringh
I want to simulate the heat and mass transfer during the drying of a granular material. A heated air is allowed to pass through a layer of the granular materials to transfer the heat from the fluid to the grains. I am using simultaneously the conjugate heat transfer (nitf) in solids transfer of diluted species (chds). With my previous settings, the simulation runs smoothly and converging. However, I want to add something important.
I would like to add a heat loss component from the grains to the moving air due to water loss from the evaporation of moisture. But I don't know how to add the heat loss in the nitf node. Every time I add a convective cooling or a negative heat flux for the heat loss, the boundary on the grains surface is no longer active. Could you advice me how to add the heat loss component from the heat transfer node.
One more thing, the solution for the mass transfer (3D Plot Number 6) is a little weird particularly at at the beginning (time=0 sec). The grains already lost moisture which is not supposedly to happen. I've noticed that this problem is caused by the meshing. When I tried to run the simulation separately for the heat transfer (nitf) and transfer of diluted species (chds), the both physics converged. But for the heat transfer, it only works best with only tetrahedral mesh. The weird result for the transfer in diluted species can be corrected with a simultaneous tetrahedral mesh plus a boundary layer mesh in the grains.
The problem is that the heat transfer physics doesn't move with a boundary layer mesh. Similarly, coupling both physics with both tetrahedral mesh and boundary layer mesh in the grains is also not moving.
Could you recommend me a technique on how to solve this problem.
I am attaching the file for you to take a look.
Thank you very much.
Best regards,
Jonathan
I want to simulate the heat and mass transfer during the drying of a granular material. A heated air is allowed to pass through a layer of the granular materials to transfer the heat from the fluid to the grains. I am using simultaneously the conjugate heat transfer (nitf) in solids transfer of diluted species (chds). With my previous settings, the simulation runs smoothly and converging. However, I want to add something important.
I would like to add a heat loss component from the grains to the moving air due to water loss from the evaporation of moisture. But I don't know how to add the heat loss in the nitf node. Every time I add a convective cooling or a negative heat flux for the heat loss, the boundary on the grains surface is no longer active. Could you advice me how to add the heat loss component from the heat transfer node.
One more thing, the solution for the mass transfer (3D Plot Number 6) is a little weird particularly at at the beginning (time=0 sec). The grains already lost moisture which is not supposedly to happen. I've noticed that this problem is caused by the meshing. When I tried to run the simulation separately for the heat transfer (nitf) and transfer of diluted species (chds), the both physics converged. But for the heat transfer, it only works best with only tetrahedral mesh. The weird result for the transfer in diluted species can be corrected with a simultaneous tetrahedral mesh plus a boundary layer mesh in the grains.
The problem is that the heat transfer physics doesn't move with a boundary layer mesh. Similarly, coupling both physics with both tetrahedral mesh and boundary layer mesh in the grains is also not moving.
Could you recommend me a technique on how to solve this problem.
I am attaching the file for you to take a look.
Thank you very much.
Best regards,
Jonathan